MDY vs VT: Correlation & Overlap
Measured on weekly returns over the past three years, SPDR S&P MidCap 400 ETF (MDY) and Vanguard Total World Stock ETF (VT) carry a correlation of 0.85, a very strong link. By holdings, the two funds overlap 3.8% by weight.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are MDY and VT?
On 3 years of weekly data the MDY/VT correlation comes out at 0.85, very strong, meaning they move nearly in lockstep. Recent behaviour matches the longer record: 0.77 over 1 year against 0.85 over 3. The 5-year figure is 0.89, and annualized covariance runs at 193.5 %².
By 3-year correlation, VT places #13 of the 359 assets tracked against MDY. Their 12-month results are close: +18.3% for MDY against +22.7% for VT. Stability stands out here, with the rolling one-year correlation confined to 0.76 through 0.91.
How is this computed?
Pearson correlation on weekly returns: ρ(A,B) = cov(rA, rB) / (σA · σB), over windows of 52, 156 and 260 weeks. Covariance is annualized (×52) and expressed in %². Full definitions on the methodology page.
MDY vs VT: side by side
| MDY (SPDR S&P MidCap 400 ETF) | VT (Vanguard Total World Stock ETF) | |
|---|---|---|
| 1-year return | +18.3% | +22.7% |
| 5-year return | +47.5% | +67.7% |
| Volatility (ann.) | 16.5% | 13.9% |
| Beta vs S&P 500 | 0.91 | 0.92 |
| Max drawdown (3Y) | -24.0% | -16.5% |
| Dividend yield | 1.02% | 1.59% |
| Expense ratio | 0.23% | 0.06% |
| Assets under management | $26.5B | $97.9B |
| Sector / category | ETF · US Small & Mid Cap | ETF · Global |
On the fund side, MDY sits in the Mid-Cap Blend category at State Street Investment Management, with $26.5B under management, 400 holdings, a 0.23% expense ratio, a 1.02% trailing dividend yield. VT is a Global Large-Stock Blend fund from Vanguard: $97.9B under management, 5308 holdings, a 0.06% expense ratio, a 1.59% trailing dividend yield.
Portfolio overlap between MDY and VT
The two portfolios are largely distinct: 3.8% of the funds' weight sits in the same underlying holdings (398 common positions). Correlation tells you they move together; overlap tells you why.
| Common holding | Weight in MDY | Weight in VT |
|---|---|---|
| ALV | 0.23% | 0.18% |
| CFR | 0.28% | 0.12% |
| CSL | 0.40% | 0.05% |
| AAL | 0.25% | 0.05% |
| G | 0.16% | 0.05% |
| ORA | 0.17% | 0.04% |
| NXT | 0.36% | 0.04% |
| ILMN | 0.93% | 0.03% |
| FTI | 0.83% | 0.03% |
| TWLO | 0.95% | 0.03% |
| CW | 0.63% | 0.02% |
| SN | 0.37% | 0.02% |
| MTN | 0.15% | 0.02% |
| ATI | 0.80% | 0.02% |
| NVT | 0.69% | 0.02% |
Largest positions held only by MDY: FHI (0.13%), WMG (0.11%). Only by VT: NVDA (4.20%), AAPL (4.00%), MSFT (3.09%), AMZN (2.36%), GOOGL (1.89%).
Overlap = sum of the smaller of the two weights across common holdings, from issuer disclosures as of 2026-08-26. Top 15 common positions shown.
Year-by-year returns
| Year | MDY | VT |
|---|---|---|
| 2022 | -13.3% | -18.0% |
| 2023 | +16.1% | +22.0% |
| 2024 | +13.6% | +16.5% |
| 2025 | +7.2% | +22.4% |
| 2026 | +16.4% | +15.2% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are MDY and VT good diversifiers for each other?
No: a correlation of 0.85 means MDY and VT tend to fall together, which is precisely when diversification is supposed to help.
FAQ
What is the correlation between MDY and VT?
The MDY/VT correlation stands at 0.85 on a 3-year window (1 year: 0.77, 5 years: 0.89), computed from weekly returns as of 2026-08-27.
Is VT a good diversifier for MDY?
No: a correlation of 0.85 means MDY and VT tend to fall together, which is precisely when diversification is supposed to help.
How much do MDY and VT overlap?
3.8% by weight, across 398 common holdings, based on issuer-disclosed portfolios as of 2026-08-26.
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Related comparisons
Hubs: MDY correlations · VT correlations
